1. Technical Field
The present invention relates to an optical scanning device having a simple structure and components thereof, in which the optical scanning device is used for an optical instrument, such as a projector, which provides images by scanning with optical signals.
2. Background
There are different kinds of projectors in the art, such as those using a liquid crystal display (LCD) or a liquid crystal on silicon (LCOS), as well as those using a micro electro mechanical system (MEMS) array mirror element including a digital mirror device (DMD). Optical scanning device should be used that is capable of scanning with an optical signal in order to produce images with such a projector.
Conventional optical scanning devices of this type typically comprise an optical system and an optical deflection mechanism for deflecting optical signals in a predetermined direction. Scanning by using laser rays reflected from a mirror is a simplified version of a combination of an optical system and an optical deflection mechanism.
Japanese Patent Laid-open No. 2006-251513 A1 discloses an optical scanning device which is a combination of a device capable of performing scans with an optical signal in a varying subscanning direction and a device capable of forming images at various focal lengths. They are cooperated with each other to provide images of high quality without any color slippage or color change.
Conventional optical scanning devices require a lot of parts and components to enlarge images. In addition, projectors using a mirror rely on reflection of light, so that the reflected light is limited by an optical system on the incident side, such as an angle of illumination. Due to various constraints and restrictions, downsizing of such devices is challenging. Additionally, high production costs are passed on to a price of a finished product, which is a factor of limiting widespread use of such devices.
Therefore, an object of the present invention is to provide an optical scanning device and components thereof with which it is possible to perform scans by using a simple configuration in order to, for example, provide a small, cost-effective projector.